Dissertation Index

This dissertation presents a new approach to “consonance” and “dissonance” in tonal jazz, specifically as manifest in solo and small-group recordings by jazz pianists from 1929 to 1966. First deconstructing the complex history of the terms, the dissertation proposes a pluralistic understanding of “consonance” that encompasses both music-syntactic and psycho-acoustic meanings in a harmonic sense. The work goes on to describe a theory of dialects of consonance that recognizes and defines contextually stable chord tones beyond the triad. Consisting of the added sixth, blues seventh, and major seventh, these three principal dialects of consonance can also include ninths and elevenths, in major and minor modes. A diachronic model accounts for the development of the dialects from sources in European classical and African influences. The work also explicates specific criteria of voicing and other sonorous factors, showing how they impact the perception of consonance.

The study then reconsiders the phonological dimension of consonance within the syntactical dimension. The dissertation argues that chords with Dominant function lead to Tonic at different hierarchic levels, and this harmonic succession by descending fifth implicates consonance. A theory of extended assemblies of scale degrees clarifies potentially ambiguous harmonies caused by rootless voicings and unaccompanied solo lines. The dissertation then defines moments of consonance based upon the rhetorical fulfillment of closure, achieved when sonorous repose is appropriately balanced in a resolution relation with its preceding dissonance. Contextual factors, such as performance rhetoric, harmonic evasion, pitch-class destabilization, and functional mixture, determine whether a moment of expected consonance is actually realized as such.

Finally, the dissertation describes a comparative methodology for the analysis of tonal structure, and systematically analyzes performances by Fats Waller, Art Tatum, Bud Powell, Thelonious Monk, and Bill Evans. Analytical results demonstrate unique features of each pianist’s harmonic approach, including ranges of dialects and choices for reharmonizations that create heightened or lessened syntactic expectation for consonance. Using models adapted from sociolinguistics, two performances demonstrate how improvisational interaction between piano and bass affects consonance. The dissertation concludes by summarizing the various aspects of dynamic consonance in tonal jazz, and offering suggestions for future applications of this research.